Risk factors and indication for dissection of right paraesophageal lymph node metastasis in papillary thyroid carcinoma

Risk Factors for Right Paratracheal Posterolateral Lymph Node Metastasis in Papillary Thyroid Cancer

Objectives

The incidence of papillary thyroid cancer (PTC) is increasing, and due to the favorable postoperative survival rates, the extent of surgery should be carefully determined, and complications during the operation should be avoided. The recurrent laryngeal nerve (RLN) divides the right paratracheal lymph node (RPTLN) into anteromedial and posterolateral compartments due to its anatomical course on the right and left sides of the neck, and the posterolateral lymph nodes are in close proximity to the RLN. Due to the risk of this complication, in this study, we aimed to determine the risk factors for the development of right paratracheal posterolateral lymph node (RPTPLLN) metastasis in PTC.

Methods

Between 2013 and 2022, patients who underwent central neck dissection (CLND) or central and lateral neck dissection due to the presence of PTC in the right lobe of the thyroid gland were included in the study. Descriptive data, along with preoperative imaging findings and postoperative pathology findings, were retrospectively evaluated.

Results

The data of 55 patients who met the criteria were statistically analyzed. Of these patients, 24 (43.6%) were male and 31 (56.4%) were female. The mean age was 47.9±17.5 years (range: 16-81). The mean tumor size was 2.17±1.43 cm (range: 0.4-7.0). RPTPLLN was observed in 13 patients (23.6%). Univariate analysis revealed that extrathyroidal extension (p=0.008), lymphovascular invasion (p=0.044), presence of right paratracheal anteromedial (RPTAMLN) metastasis (p=0.001), and presence of left paratracheal metastasis (p=0.049) were statistically significant factors. However, in the multivariate analysis, only the presence of RPTAMLN was determined to be a significant variable (p=0.035).

Conclusion

In patients undergoing surgery for PTC, the risk of metastasis in the RPTPLLN should be considered higher when there is metastasis in the RPTAMLN. We believe that formal dissection of the RPTLN should be considered for optimal evaluation in patients with tumors in the right lobe where central dissection is planned. Posterolateral dissection (PLD) should be routinely performed in the presence of clinical lymph nodes in the RPTAMLN. When a decision cannot be made, PLD may not be performed if the anteromedial tissue is examined with frozen pathology and the result is negative.

Correlation of lymph node metastasis with contrast-enhanced ultrasound features, microvessel density and microvessel area in patients with papillary thyroid carcinoma

OBJECTIVE

This study aims to investigate the relationship of cervical lymph node metastasis (LNM) with contrast-enhanced ultrasound (CEUS) features, microvessel density (MVD) and microvessel area (MVA) in patients with papillary thyroid carcinoma (PTC), and to evaluate the diagnostic value of CEUS for PTC.

METHODS

A total of 108 patients diagnosed with PTC at the First Affiliated Hospital of Jinzhou Medical University from January 2016 to December 2018 were selected and underwent preoperative CEUS of the thyroid, surgical resection and postoperative histopathological examination of their resected lesion. They were divided into a lymphatic metastasis-positive group (LNM+, n = 61) and a lymphatic metastasis-negative group (LNM-, n = 47) based on their lymph node status. The CEUS quantitative parameters, MVD and MVA, were compared between the two groups, and risk factors for LNM were analyzed by univariate and multivariate logistic regression.

RESULTS

Compared with patients with in the LNM-group, the tumor diameter and the proportion of capsule contact of patients in the LNM+group were significantly greater and the patients in this group were younger. The rise time (RT), peak intensity (PI), area under the curve (AUC), MVD, and MVA were also significantly higher in the LNM+group than in the LMN-group, while there was no significant difference in time to peak (TP), mean transit time (mTT), velocity of intensity increase (IIV), and velocity of intensity decrease (IDV) between the two groups. Univariate and multivariate correlation analysis indicated that tumor size, RT, PI, AUC, MVD, and MVA were risk factors for LNM, and ROC curves further suggested that RT had the best overall predictive performance.

CONCLUSION

Tumor size, RT, PI, AUC, MVD and MVA are risk factors for LNM in PTC. In other words, CEUS is an important non-invasive and preoperative tool for evaluating PTC, with MVD and MVA identified as vital postoperative diagnostic indicators.

Unnecessity of Routine Dissection of Right Central Lymph Nodes in cN0 Papillary Thyroid Carcinoma Located at the Left Thyroid Lobe

Objective

The lymph node posterior to the right recurrent laryngeal nerve (LN-prRLN) is an important part of the central lymph nodes (LNs). We aimed to explore the rate and predictors of LN-prRLN metastasis in cN0 papillary thyroid carcinoma (PTC) located at the left thyroid lobe.

Methods

Patients with surgically treated primary left lobe PTC were retrospectively enrolled. The metastatic distribution of LN-prRLN and postoperative complications were assessed. The association between LN-prRLN metastasis and clinicopathological variables was evaluated by univariate and multivariate analyses.

Results

A total of 857 patients were included for the analysis. Central LN metastasis was noted in 310 (35.3%) cases. The most (27.6%) and least (1.7%) commonly involved LNs were the left paratracheal LN and the LN-prRLN. In the univariate analysis, the tumor size, multifocality, the extent of extrathyroidal extension (none vs. macroscopic vs. macroscopic maximal), and perineural invasion were associated with positive LN-prRLN. In the multivariate analysis, tumor size of >40.0 mm and macroscopic maximal invasion were found as the only two independent predictors. Transient and permanent hypoparathyroidism were noted in 90 (10.2%) and 13 (1.5%) patients, respectively. Voice change was noted in 40 (4.6%) patients, and 20 patients recovered.

Conclusions

In cN0 PTC located at the left lobe, LN-prRLN metastasis was very uncommon. We found that LN-prRLN dissection is not required routinely, but should be performed if the tumor size is >40.0 mm and macroscopic maximal extrathyroidal extension is present.

A meta-analysis of risk factors for lymph node posterior to the right recurrent laryngeal nerve metastasis in papillary thyroid carcinoma

Background

Whether the lymph node posterior to the right recurrent laryngeal nerve (LN-prRLN) should be dissected is still controversial. This meta-analysis aimed to assess the risk factors for LN-prRLN metastasis in papillary thyroid carcinoma (PTC).

Methods

We retrieved relevant studies published before May 2020 from the Wanfang Data, CNKI, PubMed, Embase, Web of Science and Cochrane Library databases. Heterogeneity was assessed with the Q-test and inconsistency index and sensitivity analysis and subgroup analysis were then used to find the source of heterogeneity. Begg test and generate a funnel chart to assess publication bias.

Results

We retrieved 236 articles, 14 articles were selected as the subjects of our research. Fourteen studies involving 10,580 patients were analysed in this study. The LN-prRLN metastasis rate was 9.22% (975/10,580). The results of the meta-analysis showed that sex (P<0.001), age (P<0.001), tumour size (P<0.001), multifocality (P<0.001), capsular invasion (P=0.04), extrathyroidal extension (P<0.001), superficial central lymph node (VIa-LN) metastasis (P<0.001), and lateral lymph node (LLN) metastasis (P<0.001) were correlated with LN-prRLN metastasis.

Discussion

Male sex, age ≤45 years, tumour size >1 cm, multifocality, capsular invasion or extrathyroidal extension, and VIa-LN metastasis or LLN metastasis in PTC patients were significant risk factors for predicting LN-prRLN metastasis. B ultrasound and CT scans are expected to predict LN-prRLN metastasis in the future.

Registration

This research is registered on the PROSPERO website (registration number: CRD42020200898).

Metastasis of cN0 Papillary Thyroid Carcinoma of the Isthmus to the Lymph Node Posterior to the Right Recurrent Laryngeal Nerve

OBJECTIVE

The association between metastasis to the lymph node posterior to the right recurrent laryngeal nerve (LN-prRLN) and cN0 papillary thyroid carcinoma (PTC) located in the thyroid isthmus remains unknown; therefore, our goal was to analyze the characteristics of LN-prRLN metastasis of cN0 PTCs of the thyroid isthmus and determine its potential predictors.

PATIENTS AND METHODS

This retrospective study included patients who underwent bilateral central neck dissection between January 2018 and January 2021. The specimen was divided into five groups of prelaryngeal lymph node (LN), pretracheal LN, left paratracheal LN, lymph node anterior to the right recurrent laryngeal nerve (LN-arRLN), and LN-prRLN. Univariate and multivariate analyses were used to assess the association between the clinical pathologic variables and LN-prRLN metastases. Surgical complications were presented descriptively.

RESULTS

A total of 357 patients were included, LN-prRLN metastasis occurred in 23 (6.4%) patients, and LN-prRLN was positive only when there were other LN metastases, especially LN-arRLN metastases. Other independent risk factors for LN-prRLN included foci numbers ≥2, tumor size ≥5.0 mm, and extrathyroidal extensions. The rates of permanent hypoparathyroidism and vocal cord paralysis were 1.1% and 2.0%, respectively.

CONCLUSION

LN-prRLN metastases should not be ignored in cN0 PTC located in the thyroid isthmus; however, its dissection is a safe procedure, and the status of LN-arRLN can be a reliable predictor for LN-prRLN metastases.

Clinical and sonographic features for the preoperative prediction of lymph nodes posterior to the right recurrent laryngeal nerve metastasis in patients with papillary thyroid carcinoma

OBJECTIVE

To evaluate clinical and sonographic features predictive of lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN) metastasis in patients diagnosed with papillary thyroid carcinoma (PTC).

METHODS

We retrospectively reviewed the clinical records and ultrasound (US) images of 479 consecutive PTC patients who received total thyroidectomy or right lobectomy with central neck dissection (CND) between October 2017 and October 2019. Univariate and multivariate analyses were performed to identify clinical and sonographic features associated with LN-prRLN metastasis. Receiver operating characteristic (ROC) analysis was applied to evaluate the efficacy of clinical and sonographic features in the preoperative prediction of LN-prRLN metastasis.

RESULTS

Overall, 127 (26.5%) patients had LN-prRLN metastasis. Multivariate logistic regression analysis showed that age < 45 years (p = 0.005; OR 2.155; 95% CI 1.262-3.683), male sex (p = 0.043; OR 1.657; 95% CI 1.016-2.704), tumor diameter > 1 cm (p = 0.042; OR 1.702; 95% CI 1.019-2.842), microcalcifications (p = 0.022; OR 1.980; 95% CI 1.104-3.551), and US-detected lateral compartment lymph node (LLN) metastasis (p = 0.001; OR 2.578; 95% CI 1.500-4.430) were independent risk factors for LN-prRLN metastasis. ROC analysis revealed that the multivariate logistic regression model had good accuracy in predicting LN-prRLN metastasis, with an area under the ROC curve of 0.758.

CONCLUSIONS

Age less than 45 years, male sex, tumor diameter larger than 1 cm, microcalcifications, and US-detected LLN metastasis may preoperatively predict LN-prRLN metastasis.

Ultrasonography for the Prediction of High-Volume Lymph Node Metastases in Papillary Thyroid Carcinoma: Should Surgeons Believe Ultrasound Results?

Background

Lymph node metastasis (LNM) often occurs in papillary thyroid carcinoma (PTC); the efficacy of ultrasound for predicting high-volume lymph node metastases (LNMs) in patients with PTC remains unexplored.

Methods

The medical records of 2073 consecutive PTC patients were reviewed. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated to evaluate the efficacy of ultrasound. Risk factors for LNM/high-volume LNMs and lymph node involvement on ultrasound (usLNM) were identified by univariate and multivariate analyses.

Results

Of all the patients, 936 (45.2%) patients had LNMs, and 254 (12.3%) patients had high-volume LNMs. The sensitivity of ultrasound for detecting LNM/high-volume LNMs was 27.9% and 63.8%, respectively; the specificity was 93.1% and 90.3%, respectively. The NPV for ultrasound in detecting high-volume LNMs was 94.7%. In multivariate analysis, male sex (OR = 2.108, p < 0.001), tumor diameter > 1.0 cm (OR = 2.304, p < 0.001) and usLNM (+) (OR = 12.553, p < 0.001) were independent clinical risk factors for high-volume LNMs. Tumor diameter > 1 cm (OR = 3.036, p < 0.001) and male sex (OR = 1.642, p < 0.001) were independent clinical risk factors for usLNM; a skilled sonographer (OR = 1.121, p = 0.358) was not significantly associated with usLNM.

Conclusions

Lymph node involvement found by ultrasound has great predictive value for high-volume LNMs; the NPV is very high for patients without lymph node involvement on ultrasound. The ultrasound results do not appear to be influenced by the experience of the sonographer.

Electronic supplementary material

The online version of this article (10.1007/s00268-020-05755-0) contains supplementary material, which is available to authorized users.

A Comparison of Two Operation Methods Revealed the Risk Factors and the Necessity of LN-prRLN Dissection in Papillary Thyroid Carcinoma: A Retrospective Cohort Study in FUSCC

BACKGROUND

Although the American Thyroid Association (ATA) guidelines indicate that central lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN) should be routinely dissected, pr-RLN dissection is often neglected due to the high risk of injury to the recurrent laryngeal nerve (RLN). The purpose of this study was to investigate the risk factors associated with LN-prRLN metastasis in patients with papillary thyroid carcinoma (PTC) by preoperative examination and the indications for LN-prRLN dissection.

METHODS

A total of 1487 consecutive patients with PTC who underwent total thyroidectomy or right lobectomy plus isthmic resection with central LN dissection (CLND) were divided into two groups: patients with LN-prRLN dissection (group A) and patients without LN-prRLN dissection (group B). Clinicopathologic data were reviewed of the patients who were operated on by the same thyroid surgery team in the Department of Head Neck Surgery, Fudan University Shanghai Cancer Center (FUSCC) between August 2011 and May 2019. The relationships of LN-prRLN metastasis with clinicopathologic characteristics were analyzed by univariate and multivariate logistic regression.

RESULTS

The incidence of LN-prRLN metastasis was 34.1% (129/378). Univariate analysis showed that sex (P ≤ 0.001), tumor size (P ≤ 0.001), extrathyroidal extension (P=0.002), concurrent Hashimoto's thyroiditis (P=0.009), cLNMa (central lymph nodes anterior to the right recurrent laryngeal nerve) (P ≤ 0.001), cLNMa number (P ≤ 0.001), and lateral LN metastasis (LLNM) (P ≤ 0.001) were significantly associated with LN-prRLN metastasis in PTC. Multivariate logistic regression analysis revealed that tumor size (P=0.039), cLNMa (P=0.001), and LLNM (P=0.025) were independent risk factors for LN-prRLN metastasis in patients with PTC. Although there was no significant difference between the two groups in recurrence, we found that 4 cases relapsed in the LN-prRLN compartment in group B, while none relapsed in group A.

CONCLUSION

LN-prRLN metastasis is often identified in patients with PTC. Patients with large tumor sizes, cLNMa and LLNM are at a high risk of LN-prRLN metastasis and should be recommended for careful LN-prRLN dissection.

Risk factors for right paraesophageal lymph node metastasis in papillary thyroid carcinoma: A meta-analysis

OBJECTIVE

Prophylactic dissection of the right paraesophageal lymph node (RPELN) in thyroid cancer is controversial. We performed a meta-analysis to provide evidence for RPELN dissection in thyroid cancer.

METHODS

We searched the PubMed and Science Citation Index Expanded (SCIE) databases for relevant studies published up to January 31, 2019. The patients involved all had a pathological diagnosis of papillary thyroid cancer (PTC) and had undergone total thyroidectomy or right lobectomy with central compartment lymph node dissection. The RPELNs had been kept aside during the operation.

RESULTS

Fourteen cohort studies involving 11,090 patients with PTC were included in the meta-analysis. There was RPELN metastases (RPELNM) in 1038 patients (9.36%). The factors related to RPELNM were: age <45 years, male sex, right lobe tumor, tumor >1 cm, extrathyroidal extension, capsular invasion, right paratracheal lymph node metastasis (RPTLNM), central lymph node metastasis (CLNM), lateral lymph node metastasis (LLNM), and tumor multifocality. There was no association between RPELNM and Hashimoto's thyroiditis (HT) and inferior pole tumors or tumor in the middle of the gland. With superior pole tumors, there was even less RPELNM.

CONCLUSIONS

The clinical features related to RPELNM are age <45 years, male sex, tumor >1 cm, tumor diameter >2 cm, right lobe tumor, RPTLNM, extrathyroidal extension, capsular invasion, CLNM, CLNM ≥3, LLNM and multifocality, which should be considered when evaluating RPELN dissection.

Individualized Prediction Of Metastatic Involvement Of Lymph Nodes Posterior To The Right Recurrent Laryngeal Nerve In Papillary Thyroid Carcinoma

Purpose

We aimed to establish a prediction model based on preoperative clinicopathologic features and intraoperative frozen section examination for precise prediction of metastatic involvement of lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN) in patients with papillary thyroid carcinoma (PTC).

Methods

Clinicopathologic data pertaining to patients with PTC who underwent initial thyroid surgery between July 2015 and December 2017 were collected from electronic medical records. Multivariate logistic regression analysis was performed to identify independent predictors of LN-prRLN metastasis for incorporation in the nomogram. The performance of the model was assessed using discriminative ability, calibration, and clinical application.

Results

A total of 592 patients were enrolled in this study. The LN-prRLN metastatic positivity was 19% (95% confidence interval [CI], 15.61–21.89%). On multivariate analysis, ultrasonography-reported LN status, extrathyroid extension, Delphian lymph node metastasis, and number of metastatic pretracheal and paratracheal lymph nodes were independent predictors of LN-prRLN metastasis. The nomogram showed good discriminative ability (C-index: 0.87; [95% CI, 0.84–0.91]; bias-corrected C-index: 0.86 [through bootstrapping validation]) and was well calibrated. The decision curve analysis indicated potential clinical usefulness of the nomogram.

Conclusion

This study demonstrates that the risk of LN-prRLN metastasis in individual patients can be robustly predicted by a nomogram that integrates readily available preoperative clinicopathologic features and intraoperative frozen section examination. The nomogram may facilitate intraoperative decision-making for patients with PTC.

Risk factors for high-volume lymph node metastases in cN0 papillary thyroid microcarcinoma

Background

Lymph node metastasis (LNM) often occurs in clinical lymph node negative (cN0) papillary thyroid microcarcinoma (PTMC). The risk factors for LNM, especially for high-volume LNM, were investigated in this study.

Methods

The medical records of 1,974 consecutive PTMC patients admitted to the Peking Union Medical College Hospital (PUMCH) from 2013 to 2015 were reviewed. Their clinicopathological features were collected. Univariate and multivariate analyses were performed to identify the risk factors for LNM/high-volume LNM.

Results

Of all the patients, cervical lymph node metastases were detected in 690 patients (34.95%), and high-volume LNM was detected in 75 patients (3.80%). The results of univariate analysis revealed that sex, age, chronic thyroiditis, multifocality, and tumor diameter were significantly correlated with LNM (P<0.05) and that sex, age, multifocality, and tumor diameter were significantly correlated with high-volume LNM (P<0.05). Multivariate logistic regression analysis demonstrated that male sex [odds ratio (OR) =1.657, P<0.001], multifocality (OR =1.601, P<0.001), and tumor diameter >0.5 cm (OR =1.770, P<0.001) were independent risk factors for LNM; age of 40-59 years old (OR =0.427, P<0.001), age ≥60 years old (OR =0.291, P<0.001), and chronic thyroiditis (OR =0.562, P<0.001) were independent protective factors for LNM. For high-volume LNM, male sex (OR =2.250, P=0.002), tumor diameter >0.5 cm (OR =3.664, P=0.013) and multifocality (OR =2.034, P=0.004) were independent risk factors, whereas age ≥40 years old (OR =0.240, P<0.001) was an independent protective factor.

Conclusions

Lymph node metastases are common in cN0 PTMC, whereas high-volume LNM is rare. Active surveillance may be reasonable for patients with tumor diameter ≤0.5 cm, age ≥40 years old, female sex and isolated lesions.

Right posterior paratracheal lymph nodes metastasis is one of the predictive factors in right-sided papillary thyroid carcinoma

BACKGROUND

Lymph nodes in the right paratracheal region are separated as anterior and posterior on the basis with right recurrent laryngeal nerve. Dissection of the right posterior paratracheal lymph nodes is sometimes overlooked during a central neck dissection. Therefore, this study was designed to assess the clinicopathologic risk factors and prognostic implication for recurrence related to the presence of right posterior paratracheal lymph nodes metastasis in patient with right-sided papillary thyroid carcinoma.

METHODS

Records from 763 patients with papillary thyroid carcinoma who underwent total thyroidectomy with central neck dissection, including the right posterior paratracheal lymph nodes, between January 2007 and March 2015 were reviewed retrospectively.

RESULTS

Among 763 patients (120 men and 643 women; mean age 49.04 years) with right-sided papillary thyroid carcinoma, 127 exhibited right posterior paratracheal lymph nodes metastases. In multivariate analysis, central-compartment lymph nodes metastases (odds ratio 5.203; 95% confidence interval, 2.864-9.453) and lateral cervical lymph nodes metastases (odds ratio 3.668; 95% confidence interval, 2.375-5.667) were independently correlated with right posterior paratracheal lymph nodes metastases. Twenty-three patients (3.0%) showed loco-regional recurrence. The loco-regional recurrence rate was greater in the groups for males (P = .012), larger tumor size (>10 mm; P = .044), extrathyroidal extention (P = .002), and right posterior paratracheal lymph nodes metastasis (P < .001).

CONCLUSION

Right posterior paratracheal lymph nodes metastases are predictive factors of loco-regional recurrence, and these lymph nodes should be removed completely during a right central neck dissection in patients with right-sided papillary thyroid carcinoma with central or lateral cervical lymph node metastasis.

Risk Factors for Predicting Lymph Nodes Posterior to Right Recurrent Laryngeal Nerve (LN-prRLN) Metastasis in Thyroid Papillary Carcinoma: A Meta-Analysis

OBJECTIVE

To evaluate the risk factors for predicting lymph nodes (LN) posterior to right recurrent laryngeal nerve metastasis in thyroid papillary carcinoma.

METHODS

PubMed, PMC, EMBASE, and the Cochrane Library were systematically searched for articles published spanning 30/06/2009-30/8/2018 using multiple search terms. Thirteen articles involving 10,014 patients were reviewed in our meta-analysis. Stata 15.1 software was used for the meta-analysis.

RESULTS

The rate of LN posterior to right recurrent laryngeal nerve (LN-prRLN) metastasis was 8.65%. Univariate analysis showed that age (P = 0.001), gender (P < 0.001), tumour size (P < 0.001), lateral LN metastasis (P < 0.001), extrathyroidal invasion (P < 0.001), multifocality (P = 0.005), capsule invasion (P < 0.001), tumour location (P = 0.076), lymph nodes anterior to right recurrent laryngeal nerve (LN-arRLN) metastasis (P < 0.001), and central LN metastasis (P < 0.001) were significantly associated with the increased incidence of LN-prRLN metastasis in thyroid papillary carcinoma.

CONCLUSION

PTC patients aged <45, male, and with tumours > 1 cm, lateral LN metastasis, extrathyroidal invasion, multifocality, capsule invasion, LN-arRLN metastasis, or central LN metastasis were significantly correlated with lymph nodes posterior to right recurrent laryngeal nerve metastasis, indicating LN-prRLN dissection.

Clinicopathologic risk factors for right paraesophageal lymph node metastasis in patients with papillary thyroid carcinoma

OBJECTIVES

To investigate risk factors associated with right paraesophageal lymph node (RPELN) metastasis in patients with papillary thyroid carcinoma (PTC) and to determine the indications for right lymph node dissection.

METHODS

Clinicopathologic data from 829 patients (104 men and 725 women) with PTC, operated on by the same thyroid surgery team at the First Affiliated Hospital of Harbin Medical University from January 2013 to May 2017, were analyzed. Overall, 309 patients underwent total thyroidectomy with bilateral lymph node dissection, 488 underwent right thyroid lobe and isthmic resection with right central compartment lymph node dissection, and 32 underwent near-total thyroidectomy (ipsilateral thyroid lobectomy with contralateral near-total lobectomy) with bilateral lymph node dissection.

RESULTS

The overall rate of central compartment lymph node metastasis was 43.5% (361/829), with right central compartment lymph node and RPELN metastasis rates of 35.5% (294/829) and 19.1% (158/829), respectively. Tumor size, number, invasion, and location, lymph node metastasis, right central compartment lymph node metastasis, and right lateral compartment lymph node metastasis were associated with RPELN in the univariate analysis, whereas age and sex were not. Multivariate analysis identified tumors with a diameter ≥ 1 cm, multiple tumors, tumors located in the right lobe, right central compartment lymph node metastasis, and right lateral compartment lymph node metastasis as independent risk factors for RPELN metastasis.

CONCLUSIONS

Lymph node dissection, including RPELN dissection, should be performed for patients with PTC with a tumor diameter ≥ 1 cm, multiple tumors, right-lobe tumors, right central compartment lymph node metastasis, or suspected lateral compartment lymph node metastasis.

Predictors of lymph nodes posterior to the right recurrent laryngeal nerve metastasis in patients with papillary thyroid carcinoma: A retrospective study

The aim of this study was to identify the risk factors associated with lymph nodes posterior to the right recurrent laryngeal nerve (LN-prRLN) metastasis in patients with papillary thyroid carcinoma (PTC).A total of 81 PTC patients who underwent total/near-total thyroidectomy with LN-prRLN dissection in the Department of General Surgery at Guangdong General Hospital between June 2015 and August 2016 were assessed retrospectively. The relations of LN-prRLN metastasis with clinicopathologic characteristics of PTC were analyzed by univariate and multivariate logistic regression.The incidence of LN-prRLN metastasis in patients with PTC was 51.9% (42 of 81 cases). Univariate analysis showed that lateral LN metastasis (P = .005), VIa central LN metastasis (P = .000), pathologic tumor size (P = .000), capsular invasion (P = .002), and extrathyroidal invasion (P = .018) (P < .05) were significantly associated with the increased incidence of LN-prRLN metastasis in PTC. No significant correlations were found between LN-prRLN metastasis and other variables such as gender (P = .056), age (P = .448), clinical N stage (cN) (P = .063), tumor location (P = .336), tumor site (P = .909), right tumor existence (P = .793), and multifocality (P = .381). Multivariate logistic regression analysis revealed that VIa central LN metastasis (OR: 4.490, P = .027) was independent risk factors of LN-prRLN metastasis in patients with PTC.LN-prRLN metastasis is often indentified in patients with PTC. VIa central LN metastasis is an independent predictors of LN-prRLN metastasis, which allow for selective LN-prRLN dissection in patients with PTC.

Contrast-enhanced ultrasonography features of papillary thyroid carcinoma for predicting cervical lymph node metastasis

The present study was performed to evaluate the predictive value of contrast-enhanced ultrasonography (CEUS) for the risk of cervical lymph node metastasis (LNM) in papillary thyroid carcinoma (PTC). Between May 2014 and November 2016, 42 patients who received surgery for suspicious PTCs were enrolled in the present study. Each individual underwent CEUS with conventional ultrasound (US), preoperative US-guided fine needle aspiration and personalized surgery. Subsequently, the microvascular density (MVD) of all surgical specimens was measured. According to the results of surgical histopathology, individuals were divided into two groups: LNM⁺ (PTCs with LNM), and LNM⁻ (PTCs without LNM). Clinicopathological characteristics, CEUS enhancement patterns, perfusion parameters and measurements of MVD were compared. The correlation between quantitative variables and LNM was analyzed using Spearman's correlation analysis. Compared with that in the LNM⁻ group, patients in the LNM⁺ group were younger (P<0.05) and had a larger mean tumor size (P<0.05). The incidence ratio of patients who were ≤45 years old (P<0.05), tumors >10 mm in size (P<0.05) and capsular infiltration (P<0.05) were statistically higher in the LNM⁺ group. Following the use of a novel classification system, the ratio of PTCs with early partial hyper-enhancement was identified to be significantly higher in the LNM⁺ group (P<0.01). The mean intensity, intensity increase velocity, MVD ratio and mean intensity ratio of intratumoral/peripheral thyroid parenchyma (MIR) were statistically higher in the LNM⁺ group compared with that in the LNM⁻ group (all P<0.05). MIR was identified to be positive correlated with LNM (P<0.05). A MIR value of 0.86 was the optimal threshold of LNM in PTCs. In conclusion, LNM may rely on the local rich blood supply of PTC lesions. Partial hyper-enhancements of CEUS and higher values of MIR may suggest a high risk for LNM in PTC.

Predictive factors of right paraesophageal lymph node metastasis in papillary thyroid carcinoma: Single center experience and meta-analysis

BACKGROUND

We performed this retrospective study to identify predictors of right paraesophageal lymph node metastasis, and reviewed previous studies related to this topic.

METHODS

Between June 2005 and March 2015, 1107 patients were diagnosed with papillary thyroid carcinoma and underwent surgery at Pusan National University Hospital.

RESULTS

Right paraesophageal lymph node metastasis was observed in 171 (15.4%) patients. Multivariate analyses showed that the risk of right paraesophageal metastasis was significantly associated with tumor size, location, a higher number of metastatic central lymph nodes, and lateral lymph node metastasis. In a meta-analysis of the eligible studies, tumor size, number of metastatic central lymph nodes, and lateral lymph node metastasis showed significant relationships with the risk of right paraesophageal metastasis.

CONCLUSIONS

In patients with risk factors such as those identified in our study, the possibility of right paraesophageal metastasis should be kept in mind, and careful inspection and dissection are required.